refactor: Extract adjustScalacReleaseOptions method

Author: tgodzik

backend/src/main/scala/bloop/Compiler.scala

@@ -604,54 +604,73 @@ object Compiler {
       }
   }
 
-  private def getCompilationOptions(
-      inputs: CompileInputs,
-      logger: Logger,
-      newClassesDir: Path
-  ): CompileOptions = {
-    // Sources are all files
-    val sources = inputs.sources.map(path => converter.toVirtualFile(path.underlying))
-    val classpath = inputs.classpath.map(path => converter.toVirtualFile(path.underlying))
-    def existsReleaseSetting = inputs.scalacOptions.exists(opt =>
+  /**
+   * Bloop runs Scala compilation in the same process as the main server,
+   * so the compilation process will use the same JDK that Bloop is using.
+   * That's why we must ensure that produce class files will be compliant with expected JDK version
+   * and compilation errors will show up when using wrong JDK API.
+   */
+  private def adjustScalacReleaseOptions(
+      scalacOptions: Array[String],
+      javacBin: Option[AbsolutePath],
+      logger: Logger
+  ): Array[String] = {
+    def existsReleaseSetting = scalacOptions.exists(opt =>
       opt.startsWith("-release") ||
         opt.startsWith("--release") ||
         opt.startsWith("-java-output-version")
     )
-    def sameHome = inputs.javacBin match {
+    def sameHome = javacBin match {
       case Some(bin) => bin.getParent.getParent == JavaRuntime.home
       case None => false
     }
 
-    val scalacOptions = inputs.javacBin.flatMap(binary =>
+    javacBin.flatMap(binary =>
       // <JAVA_HOME>/bin/java
       JavaRuntime.getJavaVersionFromJavaHome(binary.getParent.getParent)
     ) match {
-      case None => inputs.scalacOptions
-      case Some(_) if existsReleaseSetting || sameHome => inputs.scalacOptions
+      case None => scalacOptions
+      case Some(_) if existsReleaseSetting || sameHome => scalacOptions
       case Some(version) =>
         try {
           val numVer = if (version.startsWith("1.8")) 8 else version.takeWhile(_.isDigit).toInt
           val bloopNumVer = JavaRuntime.version.takeWhile(_.isDigit).toInt
           if (bloopNumVer > numVer) {
-            inputs.scalacOptions ++ List("-release", numVer.toString())
+            scalacOptions ++ List("-release", numVer.toString())
           } else {
             logger.warn(
               s"Bloop is runing with ${JavaRuntime.version} but your code requires $version to compile, " +
                 "this might cause some compilation issues when using JDK API unsupported by the Bloop's current JVM version"
             )
-            inputs.scalacOptions
+            scalacOptions
           }
         } catch {
           case NonFatal(_) =>
-            inputs.scalacOptions
+            scalacOptions
         }
     }
+  }
+
+  private def getCompilationOptions(
+      inputs: CompileInputs,
+      logger: Logger,
+      newClassesDir: Path
+  ): CompileOptions = {
+    // Sources are all files
+    val sources = inputs.sources.map(path => converter.toVirtualFile(path.underlying))
+    val classpath = inputs.classpath.map(path => converter.toVirtualFile(path.underlying))
+
+    val scalacOptions = adjustScalacReleaseOptions(
+      scalacOptions = inputs.scalacOptions,
+      javacBin = inputs.javacBin,
+      logger = logger
+    )
 
     val optionsWithoutFatalWarnings = scalacOptions.filter(_ != "-Xfatal-warnings")
-    val isFatalWarningsEnabled = scalacOptions.length != optionsWithoutFatalWarnings.length
+    val areFatalWarningsEnabled = scalacOptions.length != optionsWithoutFatalWarnings.length
 
     // Enable fatal warnings in the reporter if they are enabled in the build
-    if (isFatalWarningsEnabled)
+    if (areFatalWarningsEnabled)
       inputs.reporter.enableFatalWarnings()
 
     CompileOptions

backend/src/main/scala/bloop/util/JavaRuntime.scala

@@ -14,6 +14,7 @@ import com.typesafe.config.ConfigFactory
 import com.typesafe.config.ConfigParseOptions
 import com.typesafe.config.ConfigSyntax
 import scala.collection.concurrent.TrieMap
+import scala.util.Properties
 
 sealed trait JavaRuntime
 object JavaRuntime {
@@ -74,7 +75,8 @@ object JavaRuntime {
    * appropriately.
    */
   def javacBinaryFromJavaHome(home: AbsolutePath): Option[AbsolutePath] = {
-    def toJavaBinary(home: AbsolutePath) = home.resolve("bin").resolve("javac")
+    val binaryName = if (Properties.isWin) "javac.exe" else "javac"
+    def toJavaBinary(home: AbsolutePath) = home.resolve("bin").resolve(binaryName)
     if (!home.exists) None
     else {
       Option(toJavaBinary(home))

frontend/src/test/scala/bloop/JavaVersionSpec.scala

@@ -37,7 +37,7 @@ object JavaVersionSpec extends bloop.testing.BaseSuite {
               |     value repeat is not a member of String
               |     L2:   val output = "La ".repeat(2) + "Land";
               |                              ^
-              |a/src/main/scala/Foo.scala: L2 [E1]
+              |$targetFoo: L2 [E1]
               |Failed to compile 'a'
               |""".stripMargin
         )